<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <script>
        var obj = {
            '0001': {
                'name': 'zhangsan',
                'age': 24
            },
            '0002': {
                'name': 'lisi',
                'age': 22
            }
        }
        Object.keys(obj).forEach(ele => {
            console.log(ele);
        });
    </script>
</body>

</html>